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Empty steam traps, no internals. Why?

Hi there,

My wife and I bought a property last year which used to be a very small school when first built. The steam boiler is a little oversized but hasn't been running for the 20 years as the builds been empty. I've been going over the whole system and came across a strange issue. All the radiators (15 cast iron two pipe) have empty steam traps. By that I mean, when you remove the top, there is nothing inside apart from the hole back down the the condensate line. I can't see how the system would run efficiently like this, as how would it hold the steam in the radiators to warm them and give the steam chance to condensate. Seems like the steam will just run in to the condensate line and you would lose massive amounts of energy?
Is this something you would do, to long term winterize the system so not to get moisture trapped in the radiators and corrode them over time? Or maybe someone was going to turn the system into hot water? Any ideas?
At this point if I needed to install new steam trap internals I'm guessing I have to buy the whole valve body as well or are you still able to get the equivalent replacement internal cartridges? Any help appreciated.



  • SailahSailah Member Posts: 824
    I'm guessing they were removed because they failed closed and the rads would not warm. Someone had the idea to remove cage units and voila radiators work, albeit with terrible efficiency.

    Post up the trap make and model ideally with pics and I'll tell you the correct cage unit. It's as simple as dropping it in and replacing cover.
    Peter Owens
  • johnnygreenhamjohnnygreenham Member Posts: 41
    Thanks Sailah, will do. I'm heading over there today so I'll post back tonight. Thanks again
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,140
    See if there is a vent for the air to escape from the returns, and order a bigger one from Sailah as well.—NBC
  • SailahSailah Member Posts: 824
    Just so we're clear I don't sell steam traps would just refer someone to Barnes & Jones with part numbers.
    Peter Owens
    New England SteamWorks
  • Dave in QCADave in QCA Member Posts: 1,759
    Before you get too far down this path, I would check to see if there are orifice plates installed in the unions of the supply valves on each radiator. Some of the folks who convert systems to operate as fully orificed, have the practice of removing the guts from the traps.

    If there are no orifice plates present, then I'm in complete agreement that someone may have removed them because they were failed in the closed position, but..... hard to know for sure. Now, the task is making it operate properly.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
    ratioNew England SteamWorks
  • JUGHNEJUGHNE Member Posts: 6,978
    I had a customer with your situation.
    All trap guts were gone, the valves were not operational enough to throttle the steam.

    Most valves were replaced and orifices added to all.
    The system operates in the 8 ounce range.
    Orifices are a fraction of the cost of trap replacement and do not fail or wear moving parts.
    You must drill them to the correct size to only heat 80% of the radiator. Usually that is all you need for heating.
  • JUGHNEJUGHNE Member Posts: 6,978
    Pictures of traps, inlet valves and boiler piping would be good to look at.
    Are you sure it is steam and not converted to hot water?
  • the_donutthe_donut Member Posts: 374
    I agree with @Dave in QCA and @JUGHNE. First thing I thought of was orifice plates. A lot cheaper than replacing a dozen traps. Check supply valves.
  • moneypitfeedermoneypitfeeder Member Posts: 235
    I'm interested to see if you do have orifice plates installed in the supply end. As a homeowner not wanting to constantly look after (and the expense of) traps, when mine fail, I've been leaning towards removing the traps and making orifice plates. Best of luck!
    steam newbie
  • jumperjumper Member Posts: 1,465
    Anyone try belt & suspenders approach: in addition to supply orifices they also put some restrictor(strainer,steel wool,etc) in the trap housing?
  • Jamie HallJamie Hall Member Posts: 12,947
    I'm getting slightly paranoid here. There are perhaps 50 steam traps (all Hoffman) in the main place I care for. They were installed in 1930. I think one of them has finally failed open, though the Hoffman radiator valve is set so that it isn't passing any significant amount of steam.

    Why don't my traps fail? As i say, I'm getting paranoid here...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • ratioratio Member Posts: 2,490
    Clean living and righteous thought? That's what I generally blame my success on. Or just plain awesomeness. Depends on what kind of mood I'm in.
    Dave in QCA
  • PumpguyPumpguy Member Posts: 425
    @johnnygreenham , to answer your question, so long as the supply of steam to each rad is less than it's condensing capacity, you don't need a trap. A properly sized orifice on the rad's inlet will accomplish this, as all the steam will give up it's heat and condense before reaching the outlet to the return side.

    One problem I have seen is that orifices are "dumb" i.e. fixed, and can't modulate to varying loads like a trap can.

    Others here on this board have much more experience in this area, and may report other observations.

    As @JUGHNE advised, size the orifice for 80% and you will probably be just fine.
    Dennis Pataki. Former Service Manager and Heating Pump Product Manager for Nash Engineering Company. Phone: 1-888 853 9963
  • gerry gillgerry gill Member Posts: 2,978

    I'm getting slightly paranoid here. There are perhaps 50 steam traps (all Hoffman) in the main place I care for. They were installed in 1930. I think one of them has finally failed open, though the Hoffman radiator valve is set so that it isn't passing any significant amount of steam.

    Why don't my traps fail? As i say, I'm getting paranoid here...

    Because the old Hoffman traps were like a tiger tank. New ones are like a moped.

    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

    Double D1MatthiasCanuckerdelta T
  • johnnygreenhamjohnnygreenham Member Posts: 41
    Sorry for the delayed response. Attached are a bunch of photos of the steam traps we have, the two types of regulators we have, the boiler and some pipe work. We have three loops. One loop goes clockwise round the property and serves 1/3 of the ground floor. The second loop runs anti-clockwise and services 2/3 of the ground floor. The third loop is small and runs to a 12 ft wall fin style heater in the basement (currently disconnected and capped off just after the hartford loop). Form what I can tell its still steam. It definitely last ran in 1991. I heard a rumor that it may have even have ran in the early 2000's for a test run. After than I have no idea. The previous own got into everything so i'm just going to start from scratch on most things as I'm sure pieces may be missing.
    I almost blew my own orifice trying to remove one of the regulators from the feed pipe. I opending it up. There was some pieces rattling around. You can see from the photos. I checked two other regulators and they appeared to be the same as far as internals although most of the seals on the seats are missing. I'm not entirely sure where the orifices would be located but i'm thinking that the inlet valves are open fully and a small washer looking orifice is located inside the exit of that valve (where it attaches to the radiator). Anyway, hope these photos help.

  • SteamheadSteamhead Member Posts: 13,869
    edited May 2018
    Webster 02H traps. These are pretty common, and Barnes & Jones (who @Sailah used to work for) makes replacement innards for them.

    Not sure if B&J makes parts for those valves, but Tunstall might.

    If the boiler's in good shape, it can be fitted with a modern oil or gas burner.

    Where are you located?
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • johnnygreenhamjohnnygreenham Member Posts: 41
    Thanks for the info. O2H traps, 3WH regulator valves, 2WH regulator valves are all the models installed i believe.

    Once you add up the replacement costs of the the steam trap internals and new regulators, you are getting up their in price. I see the price advantage, simplicity and reliability of the orifices are an attractive solution.
    Thanks Pumpguy for making it a little clear about why the orifice solution works. I'm going to sound stupid here but I guess I just don't know much about steam systems just yet, but I'm guessing the 80% orifice rule is 80% of the total volume of steam that, that particular radiator takes. If that's the case, how do you work that out. We probably have 8 -10 different sizes of radiators in lengths , width and columns. I'm assuming there is a chart somewhere that calculated the size of the orifice you need? Is it as simple as popping them in?

    I've almost finished rebuilding the burner. Will test it in the back yard first before I install it. My aim is to try and get as much of the system operational before I call in a steam guy to set up the burner/furnace. That part is not meant for my undertaking.

  • AMservicesAMservices Member Posts: 491
    I just replace a bunch of Webster traps and packless valves.
    Check them out here
    If you have good supply valves, they can be used to throttle the steam and you don't even need to bother orifice plates.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,140
    The only problem I see with your boiler is the order of risers from the boiler into, and takeoffs from the header to the system, in relation to the equalizer. In a modern boiler, with its small steam chest, the order should be equalizer, takeoffs to mains, and then finally risers from the boiler. This gets the steam, and any carried over water moving in one direction towards the equalizer. In your configuration, the steam will be moving in two directions, with the small riser at the end away from the equalizer.
    Because your boiler is large, with big pipes, this may not be a problem, if the boiler is not oversized, and if the pressure is kept low, (6 ounces, controlled by vaporstat), verified with a good low pressure gauge.
    If you can get the packless valves working, then they can be used to throttle the steam down to the 80% of radiator EDR. Restoring the vacuum operation would make the main venting simpler.
    Trace the route the air would take to escape with each firing, and see what sort of device is at the end. There may be intermediate traps, called crossovers along the way, and they need to work normally. With vacuum operation, the air exits the contraption through a sort of check valve, and is not allowed back in.—NBC
  • JUGHNEJUGHNE Member Posts: 6,978
    To do orifices you must know the EDR of each radiator.
    (There is info here in the library to figure that)

    Then you must determine what pressure you will operate at.
    I used the 18 ounce column to start with, if you can operate at lower pressure so much the better. If you need a little more heat for any particular rad then you can drill the hole larger.

    Search for an article by Henry Gifford entitled "How to Make a Two-Pipe Steam Heating System Really Work".
    He used 2 PSI as the basis of sizing, but I have somewhere the chart for 2 to 32 ounces and can get to it next week.
  • johnnygreenhamjohnnygreenham Member Posts: 41
    @nicholas bonham-carter. Thanks for the info. I will have to read this over and over again to understand exactly the details of what you speak but this is going to be a steep learning curve so I appreciate all this info. The boiler is oversized I believe. A rough calculation I did put my radiator BTU's around 300,000. I'll post the plate picture of the boiler.

    @AMservices. I read the link. wow. I get lost very quickly when people who know what they are talking about start naming models and specs but I picked up a few good details and will read it again this wekend.
    I really want to learn and understand the system before my wife and I spend our money on parts to rebuild this system. I'm currently confused a little about why/which direction to go in with regards to valving but I'll get there. Please keep the info posted and I'll get my learning cap on.

    Couple of simple questions - The regulator valves I have, some have a rubber seal and the others, are they packless (like the one I opened up) or did the rubber part just disintegrate?

    If i used orifice's (lead style ones I'm assuming), would I just use the current regulators fully open, lead orifice and empty steam trap?

    I'd love to understand if anyone wants to explain in lamens terms (for learners like myself) the two options, pros's and con's, I have for either using orifice plates + empty steam traps VS packless regulator valves + steam traps with cartridges. I'm struggling to understand why you would go one route or the other or is it just a preference?

    eeerr, my head is spinning.
    Kind regards, Johnny

  • PMJPMJ Member Posts: 951
    The question I will continue to ask is why do radiators ever need to be filled enough to need a trap. The original design had a big boiler modulating somewhere in the middle of its range. Likewise there was always extra radiation installed with radiators also modulating in the middle of their range. So today if you ever fill all that radiation with enough steam to send it through the outlets into the returns you are surely on the way to a good overshoot!

    There is never a reason to fill these systems with this much steam. Why continue to do it?
    1926 1000EDR Mouat 2 pipe vapor system,1957 Bryant Boiler 463,000 BTU input, Natural vacuum operation with single solenoid vent, Custom PLC control
  • jumperjumper Member Posts: 1,465
    If you value your time you'll try to get funding for thermostatic valves. If you go with orifices then undersize them. Chances are you'll end up changer fewer than if you try to size them for radiation and then go around changing for too much heat.
  • SailahSailah Member Posts: 824
    Warren Webster 02H takes a 1972 cage unit. Very common. Drop in and done. I've never played with orifice plates but I can see the appeal. I see the potential savings being eaten up in time sizing and making the plates perhaps they are readily available? And I have a machine shop!
    Peter Owens
  • Jamie HallJamie Hall Member Posts: 12,947
    The argument -- discounting some esoteric paths -- is actually rather simple. Orifices -- with no traps -- have the advantage of utter simplicity. If they are sized properly, they will almost -- but not quite -- fill the radiator at the end of a longish cycle. However, they do have to be sized properly, which can be a bit tedious, and if for some reason you don't want heat in a particular radiator, or less heat you're stuck unless you have a valve. They are also sensitive to pressure, and will work well only over a rather narrow range of pressures. Traps and packless valves, on the other hand, do involve a moving part -- the trap element -- but they are almost completely insensitive to pressure (unless they are abused) and you can turn the valve up and down to regulate the heat at your pleasure.

    Some folks seem to have a horrid time with traps failing. I don't think, personally, that this is much of a problem -- but perhaps I am just incredibly fortunate or something; as I noted in an earlier post there are about 50 of the little beggars in the main place I care for, all almost 90 years old, and there is only one which is showing signs of failing. This may be because that system is Hoffman equipped, and it is quite literally impossible to get more than an 8 ounce psi pressure differential across a trap no matter what the boiler tries to do.

    Bottom line -- I'd put the trap cages back in, as @Sailah suggests. The Barnes & Jones stuff is very well made and should last a good long time.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
    Dave in QCA
  • PMJPMJ Member Posts: 951
    As far as traps go the Mouat trap and others like it are hard to beat. They automatically shift speeds from high to low as soon as steam starts condensing in that rad and the water cup fills allowing other slower rads to catch up. The smaller hole that remains allows the rad to continue filling slowly but won't ever allow enough steam to pass to be a problem in the return. Self-adjusting, no moving parts. Pretty hard to beat.

    1926 1000EDR Mouat 2 pipe vapor system,1957 Bryant Boiler 463,000 BTU input, Natural vacuum operation with single solenoid vent, Custom PLC control
  • AMservicesAMservices Member Posts: 491
    Happy to hear you got something out of my thread and you want to Learn more.

    Packless Valves do not have gaskets. The side with the handle, is not directly connected with the plunger that open and closes the supply line.
    I Still have to rebuild several old Webster valves. Other than cleaning them up, The only piece that I need to replace is the Graphite seal on the face of the plunger, That meets the seat in the body of the valve. Some of the handles are missing.
    I know there's another heating helper on this site that has a 3-D printer he uses to make new ones.

    Consider the packless valve as your orifice.
    It's much easier opening and closing the valve to make adjustments, then it is opening the union fitting to change a orifice plate.

    On these valves the nut on top, when tighten down, locks the valve In place.

    Repair and replace packless valves, keep the steam traps for security. Then try to throttle the radiators down so the trap doesn't have to work so hard.

    With your system steam traps will be important to protect the the cross over traps, Found at the end of the steam mains.
    Cross over traps are important because they vent the air in the mains first, so steam will be at all the run outs to the radiators at the same time.

    If the cross over traps are stuck closed, all the air will have to vent through the radiators into the returns. The radiators closer to the boiler will over heat and the the ones further away will be cold.
    If their stuck open, steam will head straight for your main air vent. Depending on what your using for a main air vent, it will effect the system poorly in different ways.

    Here's how the game is played,
    Heat all the radiators evenly (to your liking)
    Keep the steam out of the returns
    Don't loose any water in the process

    You get extra points if,
    You can do it with 8 oz pressure or less
    The water has good p.h. levels
    Steam supply piping is insulated
    The system is tight enough to hold a vacuum

    Penalties are,
    Carrie over (when water siphon's out of the boiler)
    Water hammer
    Over or under firing

    What is there for a main air vent?
    Is there anything connected to the heating system that you can identify or unsure of its purpose?

    Take some wide shot pics of the boiler room.

  • The Steam WhispererThe Steam Whisperer Member Posts: 521
    A few more comments on Orifices. As Jamie said they are dead simple and, therefore much more reliable than traps. They are sensitive to pressure, as the pressure drop is fundamental to properly sizing them. However, the only typical concern is to be sure the system is not operated at an average pressure above the orifice design pressure. Otherwise the orifices work exceptionally well at a variety of pressures, keeping heating in balance. This allows you to use a system control that modulates the boiler input (or system pressure) based on load.... just like hot water reset. In a simplier form, you can also stage fire two on/off boiler and have the system heat evenly. In warm weather, the two stage thermostat only runs the first stage boiler. If the thermostat sees it cannot maintain temp with only the first stage, it will fire the second boiler to add additional capacity. Finally, you no longer have to fire the boiler based on the radiation capacity, only the building load ( again like hot water) The orifices prevent the boiler from " seeing" the complete radiator, virtually downsizing the radiation. Since most radiation is grossly oversized, you can run a smaller boiler at a lower input. This allows you to run the boiler for much longer cycles, boosting efficiency and further evening out heating.
    To learn more about this professional, click here to visit their ad in Find A Contractor.
    JUGHNEratioDave in QCA
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